In the state of the art, various methods are used for the storage of larger containers, for example, of barrels. A first method consists of arranging the containers vertically or horizontally in a rack structure, the bearing elements in this case are shelves or rack boards which are arranged at fixedly predefined spacings from each other. The spacings are, as a rule, predefined on the bearing elements, for example, on column-type supports at the corners of the rack boards or on side walls, in other cases there is no provision at all for spacing variation, in order not to impair the stability of the rack or storage facility.
In other cases, for example, when storing vertical barrels, a first layer of barrels is stored on a first bearing element, then the second bearing element with a second layer of barrels is deposited or arranged on these barrels. This method is applied in particular in the case of long-term storage, for example, in the case of distillates ageing in wooden barrels.
Neither storage method is free of disadvantages. Storing the containers in racks with fixedly pre-set spacings between the rack bases or bearing elements allows no, or only a very laborious, adaptation to different container sizes. This often has the result that in the case of smaller containers space in the storage facility is wasted, as it cannot be optimally utilized if, for example, the spacing between the bearing elements is substantially larger than the height of the containers, or if the containers are too tall, with the result that they cannot be accommodated at all.
In the case of a stacking of the bearing elements directly on the containers, on the other hand, the containers at the bottom are heavily loaded by the weight of the containers on top. The number of layers which can be stacked one on top of another is therefore limited—often only two or three layers can be stacked one on top of another—and significantly depends on the stability of the structure of the containers. If, for example, the containers are wooden barrels, such as are used for storing whisky, then the loading from above also has the result that the staves, usually held together by barrel hoops, of the barrels below bulge outwards more than envisaged, with the result that gaps which are large enough for liquid or gas to leak out form between the individual staves. As the tolerances in the manufacture of wooden barrels are greater and these are often manufactured individually, the wooden barrels often also have slightly different heights, which has the result, in the case of vertical storage, that taller barrels are loaded more heavily that shorter barrels. The quantity of liquid leaking is several percent annually, thus is financially significant. In this case, as a rule, wooden pallets are used as bearing elements.
All possible sealable hollow bodies which, on the one hand, can be stored vertically or horizontally and, on the other hand, are suitable for holding liquid, solid or powdered materials come into consideration as containers. The containers here are created such that they can be stored vertically or horizontally, for example, they can be designed cuboid. However, the containers are often designed as barrels. By a barrel is meant here, as a rule, a cylindric or cylindrical container produced from wood, metal or plastic, which can also be formed bulged, such as, for example, conventional wine barrels. Barrels without a bulge are also called drums. Such a barrel usually serves to store liquids and as a rule is filled via a bunghole, but it can also serve to store solid or powdered substances and is then, as a rule, provided with a lid.
Finally, there are also rack systems in the state of the art which are clamped between the floor and ceiling of a room. In the case of such rack systems, the supporting columns are, as a rule, designed as telescopic columns or telescopic rods, which allow a bracing against the ceiling or the floor and an adaptation, as a rule infinitely variable, to different heights. However, the spacings between the shelves are also predefined here and can be adjusted only to a limited extent. As a rule, such systems are not suitable for storing larger containers such as barrels, as the supporting structures are not designed for this.
In the case of the systems known in the state of the art, therefore, either the containers are not subjected to any loading, wherein in this case the storage space is not optimally utilized, or else they are loaded, which results in the disadvantages already named above with respect to the stackability and the stability of the containers.